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flashloan.sol

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.6.6;


import "https://github.com/aave/flashloan-box/blob/Remix/contracts/aave/FlashLoanReceiverBase.sol";
import "https://github.com/aave/flashloan-box/blob/Remix/contracts/aave/ILendingPoolAddressesProvider.sol";
import "https://github.com/aave/flashloan-box/blob/Remix/contracts/aave/ILendingPool.sol";



/**
 * @title Gordon
 * @dev Utilizes Flash loans to get free money
 */
contract Gordon is FlashLoanReceiverBase {
    
    constructor(address _addressProvider) FlashLoanReceiverBase(_addressProvider) public {}
    
    // Kovan
    // address private lendingPool = 0x506B0B2CF20FAA8f38a4E2B524EE43e1f4458Cc5;
    // Mainnet
    // address private lendingPool = 0x24a42fD28C976A61Df5D00D0599C34c4f90748c8;
    
    /**
        Flash loan 1000000000000000000 wei (1 ether) worth of `_asset`
    */
    function flashloan(address _asset, bytes memory data) public onlyOwner {
        uint amount = 1 ether;

        ILendingPool lendingPool = ILendingPool(addressesProvider.getLendingPool());
        lendingPool.flashLoan(address(this), _asset, amount, data);
    }
    
    function executeOperation(
        address _reserve, 
        uint256 _amount, 
        uint256 _fee, 
        bytes memory _params
    ) external override {
        require(_amount <= getBalanceInternal(address(this), _reserve), "Invalid balance, was the flashLoan successful?");
        // Earn some money
        for (uint i = 0; i < _params.length; i++) {
            uint8 instruction = uint8(_params[i]);
            // Do something with the instruction
        }
        
        
        // Pay back the loan :(
        uint totalDebt = _amount.add(_fee);
        transferFundsBackToPoolInternal(_reserve, totalDebt);
    }
}